<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Document</title>
</head>
<script type="text/javascript" src="lib/vue-2.6.10.js"></script>
<body>
	<div id="app">
		<h1>{{ title }}</h1>
		<input type="text" name="" v-model="qq">

		<p>{{ uname }}</p>
	</div>
	<script type="text/javascript">
		const vm = new Vue({
			el:'#app',
			data:{
				title:'vue -- watch 监听',
				qq:'',
				email:'@qq.com',
				uname:''
			},

			
			watch:{
				qq:function(){	
					let str = this.qq+this.email;
					
					this.uname = str;
				}

			}
		})


	
	</script>
</body>
</html>